Playing with Promises in Javascript

promises.js

// Promises javascript example
// Maximize asynchronous benefits!

const makePromise = (num) => () => new Promise((resolve, reject) => {
	return setTimeout(() => {
		console.log(num)
		resolve();
	}, 1000 * Math.floor(3 * Math.random()))
});

const promises = [makePromise(1), makePromise(2), makePromise(3), makePromise(4)]

// Run promises asynchronously as an example
// You'll see they end in different orders each time
// promises.map((p) => p())

// SEQUENTIAL RUN
promises.reduce((res, nextPromise) => res
	.then(() => nextPromise())
, Promise.resolve());